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<td ><a href="../qtdoc/index.html">Qt 5.12</a></td><td ><a href="qtquick-index.html">Qt Quick 模块</a></td><td ><a href="qtquick-qmlmodule.html">QML类型</a></td><td >PinchArea QML 类型</td></tr></table><table class="buildversion"><tr>
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<h3><a name="toc">目录</a></h3>
<ul>
<li class="level1"><a href="#properties">属性</a></li>
<li class="level1"><a href="#signals">信号</a></li>
<li class="level1"><a href="#details">详细信息</a></li>
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<h1 class="title">PinchArea QML 类型</h1>
<span class="subtitle"></span>
<!-- $$$PinchArea-brief -->
<p>Enables simple pinch gesture handling. <a href="#details">更多...</a></p>
<!-- @@@PinchArea -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> 导入语句：</td><td class="memItemRight bottomAlign"> import QtQuick 2.12</td></tr><tr><td class="memItemLeft rightAlign topAlign">继承自：</td><td class="memItemRight bottomAlign"> <p><a href="qml-qtquick-item.html">Item</a></p>
</td></tr></table></div><ul>
<li><a href="qml-qtquick-pincharea-members.html">所有成员的列表，包括继承成员</a></li>
</ul>
<a name="properties"></a>
<h2 id="properties">属性</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#enabled-prop">enabled</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch-prop">pinch</a></b></b><ul>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.target-prop">pinch.target</a></b></b> : Item</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.active-prop">pinch.active</a></b></b> : bool</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.minimumScale-prop">pinch.minimumScale</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.maximumScale-prop">pinch.maximumScale</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.minimumRotation-prop">pinch.minimumRotation</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.maximumRotation-prop">pinch.maximumRotation</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.dragAxis-prop">pinch.dragAxis</a></b></b> : enumeration</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.minimumX-prop">pinch.minimumX</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.maximumX-prop">pinch.maximumX</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.minimumY-prop">pinch.minimumY</a></b></b> : real</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinch.maximumY-prop">pinch.maximumY</a></b></b> : real</li>
</ul>
</li>
</ul>
<a name="signals"></a>
<h2 id="signals">信号</h2>
<ul>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinchFinished-signal">pinchFinished</a></b></b>()</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinchStarted-signal">pinchStarted</a></b></b>()</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#pinchUpdated-signal">pinchUpdated</a></b></b>()</li>
<li class="fn"><b><b><a href="qml-qtquick-pincharea.html#smartZoom-signal">smartZoom</a></b></b>()</li>
</ul>
<!-- $$$PinchArea-description -->
<a name="details"></a>
<h2 id="details">详细信息</h2>
<p><b>The <a href="qml-qtquick-pincharea.html">PinchArea</a> type was added in <a href="qtquick-module.html">QtQuick</a> 1.1</b></p>
<p>A <a href="qml-qtquick-pincharea.html">PinchArea</a> is an invisible item that is typically used in conjunction with a visible item in order to provide pinch gesture handling for that item.</p>
<p>The <a href="qml-qtquick-pincharea.html#enabled-prop">enabled</a> property is used to enable and disable pinch handling for the proxied item. When disabled, the pinch area becomes transparent to mouse/touch events.</p>
<p><a href="qml-qtquick-pincharea.html">PinchArea</a> can be used in two ways:</p>
<ul>
<li>setting a <code>pinch.target</code> to provide automatic interaction with an item</li>
<li>using the onPinchStarted, onPinchUpdated and onPinchFinished handlers</li>
</ul>
<p>Since Qt 5.5, <a href="qml-qtquick-pincharea.html">PinchArea</a> can react to native pinch gesture events from the operating system if available; otherwise it reacts only to touch events.</p>
<p><b>请参考</b> <a href="qml-qtquick-pinchevent.html">PinchEvent</a>，<a href="../qtgui/qnativegestureevent.html">QNativeGestureEvent</a> 和 <a href="../qtgui/qtouchevent.html">QTouchEvent</a>。</p>
<!-- @@@PinchArea -->
<h2>属性文档</h2>
<!-- $$$enabled -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="enabled-prop">
<td class="tblQmlPropNode"><p>
<a name="enabled-prop"></a><span class="name">enabled</span> : <span class="type"><a href="../qtqml/qml-bool.html">bool</a></span></p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This property holds whether the item accepts pinch gestures.</p>
<p>This property defaults to true.</p>
</div></div><!-- @@@enabled -->
<br/>
<!-- $$$pinch -->
<div class="qmlitem"><div class="qmlproto"><div class="table"><table class="qmlname"><tr valign="top" class="even" id="pinch-prop"><th class="centerAlign"><p><a name="pinch-prop"></a><b>pinch group</b></p></th></tr><tr valign="top" class="odd" id="pinch.target-prop"><td class="tblQmlPropNode"><p><a name="pinch.target-prop"></a><span class="name">pinch.target</span> : <span class="type"><a href="qml-qtquick-item.html">Item</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.active-prop"><td class="tblQmlPropNode"><p><a name="pinch.active-prop"></a><span class="name">pinch.active</span> : <span class="type"><a href="../qtqml/qml-bool.html">bool</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.minimumScale-prop"><td class="tblQmlPropNode"><p><a name="pinch.minimumScale-prop"></a><span class="name">pinch.minimumScale</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.maximumScale-prop"><td class="tblQmlPropNode"><p><a name="pinch.maximumScale-prop"></a><span class="name">pinch.maximumScale</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.minimumRotation-prop"><td class="tblQmlPropNode"><p><a name="pinch.minimumRotation-prop"></a><span class="name">pinch.minimumRotation</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.maximumRotation-prop"><td class="tblQmlPropNode"><p><a name="pinch.maximumRotation-prop"></a><span class="name">pinch.maximumRotation</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.dragAxis-prop"><td class="tblQmlPropNode"><p><a name="pinch.dragAxis-prop"></a><span class="name">pinch.dragAxis</span> : <span class="type"><a href="../qtqml/qml-enumeration.html">enumeration</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.minimumX-prop"><td class="tblQmlPropNode"><p><a name="pinch.minimumX-prop"></a><span class="name">pinch.minimumX</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.maximumX-prop"><td class="tblQmlPropNode"><p><a name="pinch.maximumX-prop"></a><span class="name">pinch.maximumX</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.minimumY-prop"><td class="tblQmlPropNode"><p><a name="pinch.minimumY-prop"></a><span class="name">pinch.minimumY</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr><tr valign="top" class="odd" id="pinch.maximumY-prop"><td class="tblQmlPropNode"><p><a name="pinch.maximumY-prop"></a><span class="name">pinch.maximumY</span> : <span class="type"><a href="../qtqml/qml-real.html">real</a></span></p></td></tr></table></div></div><div class="qmldoc"><p><code>pinch</code> provides a convenient way to make an item react to pinch gestures.</p>
<ul>
<li><code>pinch.target</code> specifies the id of the item to drag.</li>
<li><code>pinch.active</code> specifies if the target item is currently being dragged.</li>
<li><code>pinch.minimumScale</code> and <code>pinch.maximumScale</code> limit the range of the Item.scale property, but not the <code>PinchEvent</code> <a href="qml-qtquick-pinchevent.html">scale</a> property.</li>
<li><code>pinch.minimumRotation</code> and <code>pinch.maximumRotation</code> limit the range of the Item.rotation property, but not the <code>PinchEvent</code> <a href="qml-qtquick-pinchevent.html">rotation</a> property.</li>
<li><code>pinch.dragAxis</code> specifies whether dragging in not allowed (<code>Pinch.NoDrag</code>), can be done horizontally (<code>Pinch.XAxis</code>), vertically (<code>Pinch.YAxis</code>), or both (<code>Pinch.XAndYAxis</code>)</li>
<li><code>pinch.minimum</code> and <code>pinch.maximum</code> limit how far the target can be dragged along the corresponding axes.</li>
</ul>
</div></div><!-- @@@pinch -->
<br/>
<h2>Signal Documentation</h2>
<!-- $$$pinchFinished -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="pinchFinished-signal">
<td class="tblQmlFuncNode"><p>
<a name="pinchFinished-signal"></a><span class="name">pinchFinished</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal is emitted when the pinch area detects that a pinch gesture has finished.</p>
<p>The <a href="qml-qtquick-pinchevent.html">pinch</a> parameter (not the same as the <a href="qml-qtquick-pincharea.html">pinch</a> property) provides information about the pinch gesture, including the scale, center and angle of the pinch.</p>
<p>The corresponding handler is <code>onPinchFinished</code>.</p>
</div></div><!-- @@@pinchFinished -->
<br/>
<!-- $$$pinchStarted -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="pinchStarted-signal">
<td class="tblQmlFuncNode"><p>
<a name="pinchStarted-signal"></a><span class="name">pinchStarted</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal is emitted when the pinch area detects that a pinch gesture has started: two touch points (fingers) have been detected, and they have moved beyond the <a href="../qtgui/qstylehints.html">startDragDistance</a> threshold for the gesture to begin.</p>
<p>The <a href="qml-qtquick-pinchevent.html">pinch</a> parameter (not the same as the <a href="qml-qtquick-pincharea.html">pinch</a> property) provides information about the pinch gesture, including the scale, center and angle of the pinch. At the time of the <code>pinchStarted</code> signal, these values are reset to the default values, regardless of the results from previous gestures: pinch.scale will be <code>1.0</code> and pinch.rotation will be <code>0.0</code>. As the gesture progresses, <a href="qml-qtquick-pincharea.html#pinchUpdated-signal">pinchUpdated</a> will report the deviation from those defaults.</p>
<p>To ignore this gesture set the <code>pinch.accepted</code> property to false. The gesture will be canceled and no further events will be sent.</p>
<p>The corresponding handler is <code>onPinchStarted</code>.</p>
</div></div><!-- @@@pinchStarted -->
<br/>
<!-- $$$pinchUpdated -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="pinchUpdated-signal">
<td class="tblQmlFuncNode"><p>
<a name="pinchUpdated-signal"></a><span class="name">pinchUpdated</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal is emitted when the pinch area detects that a pinch gesture has changed.</p>
<p>The <a href="qml-qtquick-pinchevent.html">pinch</a> parameter provides information about the pinch gesture, including the scale, center and angle of the pinch. These values reflect changes only since the beginning of the current gesture, and therefore are not limited by the minimum and maximum limits in the <a href="qml-qtquick-pincharea.html">pinch</a> property.</p>
<p>The corresponding handler is <code>onPinchUpdated</code>.</p>
</div></div><!-- @@@pinchUpdated -->
<br/>
<!-- $$$smartZoom -->
<div class="qmlitem"><div class="qmlproto">
<div class="table"><table class="qmlname">
<tr valign="top" class="odd" id="smartZoom-signal">
<td class="tblQmlFuncNode"><p>
<a name="smartZoom-signal"></a><span class="name">smartZoom</span>()</p></td></tr>
</table></div>
</div><div class="qmldoc"><p>This signal is emitted when the pinch area detects the smart zoom gesture. This gesture occurs only on certain operating systems such as <a href="../qtdoc/internationalization.html#macos">macOS</a>.</p>
<p>The <a href="qml-qtquick-pinchevent.html">pinch</a> parameter provides information about the pinch gesture, including the location where the gesture occurred. <code>pinch.scale</code> will be greater than zero when the gesture indicates that the user wishes to enter smart zoom, and zero when exiting (even though typically the same gesture is used to toggle between the two states).</p>
<p>The corresponding handler is <code>onSmartZoom</code>.</p>
<p>This signal was introduced in  Qt 5.5.</p>
</div></div><!-- @@@smartZoom -->
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